#include <iostream>
using namespace std;

class Base
{
private:
    int x;

public:
    Base(int a)
    {
        x = a;
        cout << "Base constructor x = " << x << endl;
    }
    ~Base() { cout << "Base destrutor..." << endl; }
};

class Derived : public Base
{
private:
    int y;

public:
    Derived(int a, int b) : Base(a) //派生类构造函数的初始化列表
    {
        y = b;
        cout << "Derived constructor y=" << y << endl;
    }
    ~Derived() { cout << "Derived destructor..." << endl; }
};
int main()
{
    Derived d(1, 2);
    system("pause");
    return 0;
}